Add rinsed and drained kidney beans, mushrooms pieces, undiluted tomato soup and tomatoes with the liquid
Add the rest of the chili powder (2 tablespoons), oregano (1 teaspoon), salt (1 teaspoon), pepper (1/4 teaspoon), sugar (1 teaspoon), and garlic (optionally) (3 teaspoons).
Stir ingredients together well.
Cover and simmer for one hour, stirring occasionally.
Remove cover and simmer for 30 minutes or more, stirring occasionally.